Pneumatic action for musical instruments.



V. L. JONES.

PNEUMATIC ACTION FOR MUSICAL INSTRUMENTS.

APPLICATION FILED APR. I0. 1913.

1,201,306, Patented Oct. 17, 1916.

I I I 'j/ 6 I 2. j C a 1191. C /i c' Wtn 6356/8 f 2 to) Qi/ pzax 7??11/271 as UNITED STATES PATENT OFFICE.

VEBN Id. JONES, OF DETROIT, MICHIGAN, ASSIGNOR TO THE FARRAND COMPANY,OF DETROIT, MICHIGAN, A CORPORATION OF MICHIGAN.

PNEUMATIC ACTION FOR MUSICAL INSTRUMENTS.

Application filed April 10, 1913.

T 0 all whom it may concern:

Be it known that I, VERN L. JoNns, a citizen of the United States ofAmerica, residing at Detroit, in the county of IVayne and State ofMichigan, have invented certain new and useful Improvements in PneumaticActions for Musical Instruments, of which the following is aspecification, reference being" had therein to the accompanyingdrawings.

My invention relates to pneumatic actions for automatic pianos and moreparticularly to that type of action composed of a series of motor andvalve units.

The invention consists in the provision of a simple and efiicientstructure which may be easily and cheaply manufactured; in a structurethat is compact and reduces the width of the action; in a constructionthat is not easily affected by change in atmospheric conditions, and incertain combinations and arrangements of parts as will more fullyhereinafter appear.

In the drawings, Figure l is a. vertical, central section through one ofthe pneumatic units embodying my invention; Fig. 2 is a similar viewtaken in a difierent plane; and Fig. 3 is a top plan view.

A designates one of the units composed of a valve section or unit B anda key-actuating pneumatic C, and D is the wind-trunk to which the unitsof one series are attached. Each valve section comprises a casing E,preferably cylindrical and formed of metal, and primary and secondarypneumatics arranged therein. Thus the primary pneumatic is formed of achest section having a lower member F and an upper member G. The lowerend of the casing is closed by a metallic cap I-I provided with achamber I to which a conduit J that leads to the traokerboard, isconnected. A suitable washer K is interposed between the cap H and theflange L upon which the cap is seated, so as to seal the jointtherebetween.

M is a diaphragm suitably attached to the upper face of the cap H andclosing the top of the chamber I and N is a valve positioned within arecess or chamber 0 and controlling a passage P.

R is a second valve connected to the stem a of the valve N andcontrolling communication between the passage P and a chamber Q in theupper member G. The chamber 0 is connected by means of a conduit S inthe Specification of Letters Patent.

Patented Oct. 17, 1916.

Serial No. 760,255.

chest section of the primary pneumatic and an aperture T in the casingwith the windtrunk. Leading from the passage P is a conduit U that opensinto the diaphragm chamber V of the secondary pneumatic, this diaphragmchamber being formed in the top face of the upper member G. Thediaphragm W of the secondary pneumatic is arranged between the adjacentfaces of the primary and secondary chest sections and preferably isattached to the upper member G of the primary pneumatic. The member X ischambered at Y and the latter is in constant communication with thewindtrunk by a passage Z and an aperture A in the casing E.

B is the upper member of the secondary pneumatic chest, herein shown asformed of a ring section C and a metallic disk D. Communication betweenthe chamber E of the member B and the chamber Y is controlled by a valveF and attached to be simultaneously operated with the valve F is asecond valve G that controls an aperture H in the disk D.

I is a clamping ring having a screwthreaded engagement with the casing Eand adapted to clamp the several parts within the casing. The jointsbetween the cap and the ring C and between the latter and the me%ber Xare sealed by packing rings U The chamber Q, is in communication withthe atmosphere by means of a passage L that alines with an aperture M inthe side of the casing E, and the joint between the casing and themember G around the aperture M is sealed by means of a packing ring Npreferably made of felt, seated in a recess N in the member G. Theconduit J is provided with a bleed connection (not shown) which is incommunication with the exhaust mechanism.

In operation the parts-are normally as shown in Fig. 1, and since thechambers O I and Y are in communication with the exhaust mechanism,these chambers will be at less than atmospheric pressure. Also since thediaphragm chamber V is in communication with the chamber 0 by means ofthe passage P and conduit U, the diaphragm chamber will be at less thanatmospheric pressure. Upon the opening of a port in the tracker-boardwhich leads to the tube J, the chamber I will be placed in communicationwith the atmosphere, thereby causing the raising of the diaphragm Mwhich will close the valve N and open the valve S. Upon the opening ofthe valve S the chamber Q, which is in communication with the atmosphereby way of the port L and aperture Ml will be connected to the diaphragmchamber V by means of the passage P and conduit U, expanding thediaphragm, closing the valve G, and opening the valve Fi The opening ofthe valve F placesfthe key-actuating motor C in con'nnunication by meansoi? apertures Q R and the aperture S, with the chamber Y and therefore,in direct communication with the wind-trunk D. The vacuum will collapsethe pneumatic C in the usual manner. Upon the closing of the port in thetracker-board that leads to the tube J, the bleed connection for thetube J will exhaust the chamber I, permitting the valves to return totheir normal position. Upon the opening of the valve G the pneumatic Cis placed in communication with the atmosphere through the aperture H,chamber E and ports Q R.

It will be noticed that when the port S is open the key-actuatingpneumatic is in communication with the wind-trunk by a very shortpassage. This materially in creases the speed at which the instrumentmay be played, since the shorter the passage, the quicker will thevacuum of the wind-trunk act upon the key-operating pneumatics.

The construction of valve section hereinbefore described permits theparts of the primary and secondary pneumatics to be readily assembledwithin or removed from the casing. When assembled the pneumatic partsare supported by the flange L and are secured in place by a singleclamping memberthe ring I. In making up the unit the washer L isattached to the bottom face and the diaphragm M to the top face of themetallic cap H; the pouch or diaphragm is secured to the member G andafter the valves of the primary pneumatic are engaged with the member Fthe latter and the member G are cemented together. The pneumatic ispositioned in the casing and the member X arranged thereon. The valvesof the secondary pneumatic, the ring 0, washers K J and disk D areproperly engaged with each other. Then the ring I is screwed into theupper end of the casing to clamp the several parts in place. As all thejoints between the abutting faces of the primary and secondarypneun'iatics are sealed, and as the washers l1 and J seal the joints ofthe end members of the casing,-

an exceedingly acc rate fit between the side walls of the chest sectionsand the sides of the casing is unnecessary.

The wind-trunk D is secured to the casing E by means of a screw Apassing through an aperture in the trunk and having the inner endengaging a threaded aperture B in the casing. A suitable packing as C isinterposed within the trunk and adjacent the connection between thetrunk and the casing so as to properly seal the joint there between.

Vhat I claim as my invention is In a pneumatic action, a valve unit,including a casing and primary and secondary pneumatic chests arrangedin said casing, a wind-trunk on one side of said casing adapted tocommunicate with said primary and secondary pneumatics, and akey-actuating pneumatic on the opposite side of said casing adapted tocommunicate with said secondary pneumatic, the passage between saidkey-actuating pneumatic and said windtrunk being comparatively short anddirect.

In testimony whereof I ailix my signature in presence of two witnesses.

VERN L. JONES. lVitnesses:

M. J. BELKNAP, James P. BARRY.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents.

Washington, I C.

